1. Technical Field
Embodiments of the present disclosure relate to video encoding and decoding technology, and more particularly to a discrete cosine and inverse discrete cosine transform circuit.
2. Description of Related Art
Discrete cosine transform and inverse discrete cosine transform (DCT and IDCT) are respectively used in the encoding and decoding of video data, known as video codec. The video data generally comprise a series of images, each composed of a plurality of 8*8 pixel blocks. Encoding of the video data includes performing the DCT on each block to transform the pixel blocks to frequency domain data. Decoding of the video data includes performing the IDCT on the frequency domain data to transform the frequency domain data to pixel data. Generally, a DCT/IDCT operation with two dimensions (2-D) can be executed by performing transform operations on a row or a column with one dimension (1-D) and then on a column or a row with another dimension. The DCT/IDCT operation includes numerous butterfly operations.
A wide variety of video codec protocols, such as H.264, WMV9, and MPEG-2 are employed. Encoding or decoding according to these video codec protocols requires DCT/IDCT operations. However, operations related to each specific video codec protocol differ greatly from one another and must be respectively performed by different circuits. As a video device is required to support most or all of this variety of video codec protocols, a corresponding plurality of different circuits is required, such that the video device must be configured with large scale circuits, complicating design and elevating costs. There remains a heretofore unaddressed need to overcome the limitations described.